Ubuntu wont let me download anything at all,not from Ubuntu or the Internet.
Every time I try it keeps popping up this:

Archive: /home/dave/Downloads/iTunes64Setup.exe
[/home/dave/Downloads/iTunes64Setup.exe]
End-of-central-directory signature not found. Either this file is not
a zipfile, or it constitutes one disk of a multi-part archive. In the
latter case the central directory and zipfile comment will be found on
the last disk(s) of this archive.
zipinfo: cannot find zipfile directory in one of /home/dave/Downloads/iTunes64Setup.exe or
/home/dave/Downloads/iTunes64Setup.exe.zip, and cannot find /home/dave/Downloads/iTunes64Setup.exe.ZIP, period.

Does it happen with anything besides .EXE files? This looks like the message that the archive manager pops up when it can't open Windows programs. The other thing you might try is installing WINE, though I can't promise how well iTunes will work in it.
–
zpletanJun 10 '12 at 19:06

Did you choose to automatically open downloaded files in your browser settings?
–
TakkatJun 10 '12 at 19:29